Recent advances in the use of summed probability distribution (SPD) of calibrated 14C dates have opened new possibilities for studying prehistoric demography. The degree of correlation between climate change and population dynamics can now be accurately quantified, and divergences in the demographic history of distinct geographic areas can be statistically assessed. Here we contribute to this research agenda by reconstructing the prehistoric population change of Jomon hunter-gatherers between 7,000 and 3,000 cal BP. We collected 1,433 14C dates from three different regions in Eastern Japan (Kanto, Aomori and Hokkaido) and established that the observed fluctuations in the SPDs were statistically significant. We also introduced a new non-parametric permutation test for comparing multiple sets of SPDs that highlights point of divergences in the population history of different geographic regions. Our analyses indicate a general rise-and-fall pattern shared by the three regions but also some key regional differences during the 6th millennium cal BP. The results confirm some of the patterns suggested by previous archaeological studies based on house and site counts but offer statistical significance and an absolute chronological framework that will enable future studies aiming to establish potential correlation with climatic changes.

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Abstract1. Isotope analysis has high potential for understanding fish ecology and food-web structure in aquatic ecosystems. The utility of isotope analysis will be greatly improved if we can reconstruct the chronology of several isotopes at multiple growth stages of individual fish. However, no practical methods exist for reconstructing the chronology of light-element isotopes (e.g. δ 13 C, δ 15 N, δ 34 S, andHere, we present and test a new analytical approach for reconstructing the isotopic ratios of light isotopes at multiple life-stages in teleost fishes.2. We sampled an anadromous salmon species, masu salmon Oncorhynchus masou (n = 3), along with water from its natal stream and from the ocean. We subdivided the vertebral centra of the salmon equally into 10 sections and extracted bone collagen from each sample. We then measured the stable sulphur isotope ratios of each vertebral section and compared them with δ 4. Our results show that the vertebral centra of teleost fishes record isotopic information from juvenile to adult life stages. We suggest that our method can provide reproducible isotopic chronology, even in teleost fishes smaller than 50 cm. This method can be used in isoscape studies and in studies of the ecology of marine teleost fishes. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. K E Y W O R D S